Is Earth a blue planet?
Composition and Structure of the Oceans. Planet Earth has been called the "Blue Planet" due to the abundant water on its surface. Here on Earth, we take liquid water for granted; after all, our bodies are mostly made of water. However, liquid water is a rare commodity in our solar system. Is Earth a blue planet or green planet? Neptune: The Blue Planet. Why is the blue planet Earth? Seen from space, the Earth is blue.